Pipe pusher



Jan. 8, 1929.

c. R. HARDING PIPE PUSHER' Filed Nov. l8, i926 C. ETIGFdI'ng INVENTOR wmlvw ATTORNEY Patented Jan. 8, 1929.

UNITED STATES PATENT o'rrics.

CLYDE R. HARDING, OF COUNCIL BLUFFS, IOWAF PIPE PUSHER.

Application filed November 18, 1926. Serial No. 149,138.

I object of my invention is the provision of an attachment whereby a hole ofsufficient size may be made in the soil for inserting tile. Other objects will be mentioned in the following description.

Referring now to the drawings, Figure 1 is a'view in perspective of the entire pipe pusher and the head.

Figure 2 is a view in perspective of the carriage on a somewhat larger scale than that of Figure 1. l Figure 3 is a fragmentary view in plan and including portions of the base and carriage and showing particularly. the relation of the pawls'to the rack.

Figure 4 is a view in lengthwise section of the head and push pipe, and showing also the pipe for conducting water under pressure to the head.

The reversible pipe pusher 'includes the base 10 and the carriage 11. Thebase 10 has side members 12 ofangle steel, the side members'being secured in spaced apart and paral lel relation by means of the straps 13 at the ends of the side members and by a strap 14 midway between the straps '13. The number of thesestraps may, of course, be varied at will but it is essential that the structurebe firm and rigid enough for the work which it'is intended to do. The straps 13 and 14 project on both sides of the base so that they may be'firmly anchored to the earth to pre-' vent their movement during the operation of the pipe pusher. 1

Secured to the side members 12 and on the outer sides thereof are additional straps 15 which are bentso as to space portions of them away'from. the sideinembers 12 as shownin Figure 1. The pawl carrying U-shaped levers 16 and 17. enter the spaces between the side'members 12 and the straps 15 and are secured theretojb y means: of the pivot pins 18. In order to reinforce these levers rein forcing straps 19 are secured to the levers 17 and to the pivot pins 18, the straps 19 being positioned outside of the straps 15. The levers 16 and 17 have pawls 20 pivotally secured thereto at 21 so as to swing freely.

The pawls 20 are symmetrical as shown in Figure 3, for reasons which will besubsequently explained. The pawls are positioned in close proximity to the inner walls of the vertical portions of the side members 12. The levers 16 and 17 areactuated by means oftlie lever 22 which is pivoted at 23 to the side members 12 and to the straps 15, and which acts on the levers 16 and 17 through the links 24. The lever 22 is also U-shaped j and it terminates at its upper end in the handle member 25 which may be either grasped by the hands or which may receive the end of the gas pipe extension.

' The carriage shown in Figure 2 is designed for sliding movements in the base between the side members 12. It consists of a pair of rack portions 26 which cooperate with the pawls 20 and of a device forrigidly securing the pipe which is to be pushed. The racks 26 are cut in the base at its lateral edges, and between the racks the base is provided with two pairs of upwardly projecting ears 27. The I dogs 28 have collar portions 29 fitting'be tween the ears-of a pair and they are secured to the ears by means of removable pivot pins 30. Bothof the dogs are weighted by means of weights 31 whichare integral with the dogs 28 andthe collars 29. The pipe 32 is firmly gripped by means of these dogs and any pushing action on thejcarriage' in a forward direction increases this grip.

' In use, the base is firmly anchored to the.

ground and'the carriage 11 is loosely positioned in the base. The pipe'32 is then clamped in the carriage 11, in the manner shown in Figures 1 and 2.5The actuation of the lever 22'will cause the pawls 20 to be moved forwardly and backwardly, and each forward. motion of the pawls acting on they racks 26 causes the forward movement of the carriage and with it the pipe 32. The rearward, movement of the pawls simiply brings them into engagement with another notch of the rack where they willbe in position for another forward step when the lever 22 again moves forwardly. The reciprocation of the lever 22 may be continued until the end of the rack 26 is reached at which time the dogs 28 must be released to permit the carriage to be moved rearwardly until the pawls 20 are again in engagement with the forward notches of the racks 26. The re lease of the dogs 28 is an easy matter since the weights 31 may serve as levers for lifting the dogs out of engagement.

' Such pipes as that shown at 32 are usually pushed through the soil in a more or less hori zontal direction and this can easily be done by successive-steps in the manner above de scribed. When it is deslred to install a lead pipe, the steel or iron pipe should first be forced through the ground in the manner already described and it should then be withdrawn with the end of the lead pipe secured to it. In this manner the lead pipe is drawn through a hole which is already made so that the lead pipe is not subjected to a rough usage for which it is not adapted. The pipe 32 may be withdrawn from the hole by resetting the base 10, but the use of'the reversible pipe pusher herein described makes suchresetting unnecessary. If the pawls 20 are swung .abouttheir pivots they will, of course, act

in the opposite direction and will exert a pull in the opposite direction on the carriage 11. In order to hold the pipe in the'carriage on the reverse pull the carriage may be turned endto end in the base 10 or the. pivot pins 30 30 may be withdrawn in order to reverse the dogs 28. The reciprocation of the lever 22 will then result in the withdrawal of the pipe'32 from the hole whichit has formed. It is frequently necessary that a hole be formed which is larger than is practicablethe use of pipe as above described. For

. such situations I have provided a special form of headas shown at 33 in Figures 1 and p I 4. This head is in the form of a double cone which is cast directly on a section of pipe 34. The-pipe 34: has a reduced end'35. which serves as a nose for the head 33. The rear end of the head is] open and is interiorl'y screwthreaded for the reception of the end of the push pipe 36, the push pipe being the one which is secured in the pipe pusher by the dogs 28.' The head 33' is provided wlth a wall'37 which servesas an abutment for the end of the pipe 86. f

The most common use to which pipe push; ers areput the laying of pipe without dig.- ging trenches. j Trench digging is always expensive and in most cases it is impossible.

the railroad companies. will easily lay the pipe without disturbing the road bed. Around railroad shops 1t 1s,

"often necessary to lay a water line, steam line or waste line undertracks and th s can easily be done by the use of the pipe pusher.

' Aside from the more common use the plpe pusher as above described has a number of other very important' uses. In the connections with water mains, lead pipe is usedalmost exclusively and lead pipe cannot be pushed. With the usual form of pipe pusher .it is possible to force the iron or steel plpe through the ground, to then reverse and reset the machine and to finally draw the lron pipe fromthe hole with the end of lead pipe secured thereto. lVith the machine as above described the resetting of the machineis not necessary as its actlon may be reversed 1n a This reversing action 1s few'mifnutes time. 7 partlcularly lmportant when t 1s desired to remove corroded pipe and toreplace it with In such a case the corroded plpe new pipe. is first withdrawn by the plpe pusheiy ts action is then reversed and the new pipe is pushed through the opening left by the old.

The pipe pusher v Machines of this kind, of course, have their limitations as regards the size of the pipe which is to be pushed. Beyond a certain diameter it is impracticable to push pipe as the.

initial cost and the weight of the machine would be prohibitive. Tile and. cast iron pipe are usually laid in trenches but with the use of the special head as abovedescribed it is possible to lay tile and cast iron pip'ehaving diameters of up to15 inches. For this use ahead of the proper diameter is forced through the earth in the manner described and the tile is then drawn through the hole formed by the head, the drawing being done either by hand or by the pipe pusher on the reversevaction, Theresist-ance of the soil to the pusher head varies with the square of the diameter of the head. v In thev pipe pusher as above described the enormous resistances of the soil are overcome in two ways. The ma.-

chine itself is rugged enough to Withstand these resistances so that it is only necessary to increase the leverage- Thislcan easilyf be done'by using a length of gas'pipe. Then too, the resistances'may be materially reduced 7 by means ofthe water jet which hasa twofold function." It lubricatesthe walls of the hole I and it removes much of the clay which is in the path of the head... 7 I

Having thus described my invention insuch full, clear, and exact terms that its construction' and operation will be readily understood by-others skillediin the art to which itper tains, what I claim as new and" desire to se cure by Letters Patent of'the United Statesis A pipe. pusher, comprising a base member having upturnedlongitudinal side flanges a carriage slidably mounted in the base member between said flanges and having a rack at each side, weighted dogs pivotally mounted in the carriage for gripping a pipe therein, spaced apart U-shape pawl levers pivoted to 5 the opposite side flanges of the base member and straddling the base member and said carriage, pawls pivoted to the opposite inner sides of said pawl levers in line and for engage- 'ment with said racks of the carriage to ad- 10 vance the latter in the base member, said pawls being symmetrical and adapted to be swung to opposite sides of their pivots to carriage, a U-shape handle pivoted to the opposite side flanges of the base member between the pawl levers and straddling theb-ase and carriage, and side links connecting the opposite sides of the handle to the opposite sides of the pawl levers to simultaneously actuate all of the pawls from the handle.

In testimony whereof I affix my signature.

CLYDE R. HARDING.

'change the direction of advancement of the 

